The Impact of Human Activity on Whale Populations#
For decades, the vast and mysterious presence of whales has captivated both scientists and the public alike. These marine giants serve vital ecological functions, from regulating food webs to contributing to the global carbon cycle. Yet in the last century, the pressures exerted by industrial-scale fishing have brought their survival into question. As demand for seafood rises, concerns grow over the consequences this industry may have on the health of whale populations worldwide. (Block & Amudson, 2020)
While oversea transport and fishing is crucial for global trade, global food security, and coastal livelihoods, its side effects are increasingly hard to ignore. One particularly serious issue is whale bycatch, the accidental capture of whales in fishing gear. Combined with overlapping marine traffic and habitat disruption, these pressures raise urgent questions about how to balance marine resource use with conservation. Despite growing awareness, the scale and impact of these interactions remain difficult to quantify. (Moore et al., 2012)
To shed light on this issue, we analyzed data from multiple marine datasets covering whale bycatch, whale and ship activity, and fishing activity across several regions and years. Our goal was to understand the scale and geography of interactions between whales and human activity on sea. In doing so, we aimed to identify which whale species are most exposed, which regions pose the highest risk, if the problem has gotten somewhat better over the years, and how data-driven policy could help protect marine life while supporting sustainable fishing practices.
The Impact of Fishing Industries#
To understand the pressures facing whale populations today, it’s essential to first examine the broader trajectory of the fishing industry itself. The graph below illustrates the dramatic growth in global fishery production over the past six decades, a trend that reflects not only rising global demand for seafood but also the intensification of industrial fishing practices.
%run gdp.ipynb
From 1960 to the late 1980s, global capture fisheries production experienced a steady and steep rise, growing from around 300 million metric tons to over 700 million. This surge coincided with post-war technological advances in fishing vessels, sonar tracking, and cold storage, tools that allowed fleets to venture farther and stay out longer. The 1980s and 1990s marked a second, steeper climb, with production peaking around 2000, approaching nearly 1 billion metric tons annually (Pauly et al., 2005).
But the graph also tells a subtler story: since around 2000, global capture production has plateaued, with slight fluctuations but no sustained increase. This leveling off suggests that most of the world’s major fisheries have reached or exceeded their sustainable limits. Declines after 2015 in some years may even hint at early signs of nature consideration or stock collapses in certain regions.
For whales, this upward curve in fishing activity directly correlates with a rise in threats such as bycatch, gear entanglement, and habitat disruption. More fishing effort means more gear in the water, more ship traffic, and less available food in some shared ecosystems. Importantly, this global trend does not represent a uniform threat; certain regions and species are more exposed than others, as other graphs in this study show.
In short, this graph captures the historical momentum behind today’s marine pressures. While fisheries are essential for food security and livelihoods, their exponential growth over the past half-century has created widespread and systemic risks for marine megafauna like whales. Understanding these long-term trends helps frame the urgency for sustainable management, not just of fisheries, but of all life that shares the sea.
To understand the scope of this issue, we examined global fisheries production data. The map below shows total fisheries output by country, zoomed in to reflect the 95% range to avoid extreme outliers:
%run gdp2.ipynb
We observe that countries with vast coastlines or industrialized fleets, such as those in East Asia, North America, and parts of Africa, tend to dominate production. This aligns with what we know about the scale of fishing operations, and also with where whale populations often come into conflict with these activities.
From a data perspective, when plotted over time, total global fisheries production shows a sharp rise from the 1950s, peaking around 2000, and then stagnating. However, this plateau does not reflect reduced fishing pressure. Instead, it could imply that we’ve reached ecological limits in many regions. Despite stable yields, fishing effort, gear in the water, time at sea, intensity has not decreased.
One of the most devastating outcomes of industrial fishing is whale entanglement in gear such as gillnets, longlines, and trawls. These incidents, often fatal, are difficult to track and underreported, yet they are now among the leading causes of whale mortality.
This map, although not explicitly marking whale-human incidents, helps identify hotspots of risk: where large-scale fisheries intersect with known whale habitats. Regions with dark blue shading, especially parts of Asia and the Americas, are critical areas where both production and ecological risk converge.
%run ship_strike_risk.ipynb